Electrical switching apparatus, and trip actuator assembly and reset assembly therefor

Abstract

A trip actuator reset assembly for a circuit breaker includes a cradle assembly, a reset lever, a trip actuator, and a rigid element. The cradle assembly is pivotably coupled to the circuit breaker pole shaft, and includes a number of springs. A pivot pivotably couples the reset lever to the circuit breaker housing. In response to a trip condition, an actuating element of the trip actuator moves a first end of the reset lever. The rigid element is pivotably coupled to the housing proximate a second end of the reset lever. To reset the trip actuator, a guide member guides the cradle assembly into engagement with the rigid element which pivots the reset lever. The first end of the reset lever then resets the trip actuator. After reset, if the cradle assembly continues to move, then the springs accommodate the additional motion.

1. A trip actuator reset assembly for an electrical switching apparatus including a housing, separable contacts enclosed by said housing, and an operating mechanism structured to open and close said separable contacts, said operating mechanism including a pole shaft, said trip actuator reset assembly comprising:
 a cradle assembly including a first end structured to be pivotably coupled to said pole shaft, a second end disposed opposite and distal from the first end, and a number of springs disposed between the first end and the second end, said cradle assembly being structured to be movable among a first position corresponding to said separable contacts being closed, and a second position corresponding to said separable contacts being open; 
 a reset lever including a first end, a second end disposed opposite and distal from the first end of said reset lever, and a pivot structured to pivotably couple said reset lever to said housing; 
 a trip actuator including an actuating element which, in response to a trip condition, is structured to move the first end of said reset lever; 
 a rigid element structured to be pivotably coupled to said housing proximate the second end of said reset lever; and 
 a guide member, 
 wherein, after said trip condition, said actuating element of said trip actuator is structured to be reset, 
 wherein, when said cradle assembly moves from said first position toward said second position, said guide member guides said cradle assembly into engagement with said rigid element which pivots said reset lever, 
 wherein, when said rigid element pivots said reset lever, the first end of said reset lever moves said actuating element of said trip actuator, thereby resetting said trip actuator, and 
 wherein, after said trip actuator has been reset, if said cradle assembly continues to move beyond said second position, then said number of springs of said cradle assembly accommodate any additional motion of said cradle assembly. 
 
   
   
     2. The electrical switching apparatus of  claim 1  wherein said housing of said electrical switching apparatus includes a mounting surface, a first side plate extending outwardly from said mounting surface, and a second side plate extending outwardly from said mounting surface; wherein said guide member includes a first end, a second end disposed opposite and distal from the first end of said guide member, and an elongated body extending between the first end of said guide member and the second end of said guide member; and wherein said elongated body is structured to extend between said first side plate and said second side plate. 
   
   
     3. The electrical switching apparatus of  claim 2  wherein said first side plate includes a first side and a second side; wherein said actuating element of said trip actuator is structured to be disposed on the first side of said first side plate; and wherein said pivot of said reset lever is structured to be pivotably coupled to the first end of said guide member at or about the first side of said first side plate. 
   
   
     4. The electrical switching apparatus of  claim 3  wherein said reset lever further includes a bias element; wherein said first side plate further includes a hole; wherein the second end of said reset lever is structured to extend from the first side of said first side plate through said hole of said first side plate and beyond the second side of said first side plate; and wherein said bias element is structured to be disposed within said hole of said first side plate, in order to bias the second end of said reset lever away from said actuating element of said trip actuator. 
   
   
     5. The electrical switching apparatus of  claim 3  wherein said cradle assembly comprises a first side structured to extend from said pole shaft toward the second end of said cradle assembly, a second side disposed opposite and spaced from the first side of said cradle assembly, a first cross member disposed proximate the first end of said cradle assembly, a second cross member disposed at or about the second end of said cradle assembly, and at least one elongated member fixedly coupled to said second cross member and extending through said first cross member; wherein said first cross member extends between the first side of said cradle assembly and the second side of said cradle assembly; wherein said first cross member does not move independently with respect to the first side of said cradle assembly and the second side of said cradle assembly; and wherein said second cross member is structured to extend between and be pivotably coupled to said first side plate and said second side plate, thereby providing a fixed pivot point for said cradle assembly with respect to said first side plate and said second side plate. 
   
   
     6. The electrical switching apparatus of  claim 5  wherein, when said cradle assembly is moved toward said second position, the first side of said cradle assembly, the second side of said cradle assembly, and said first cross member extending therebetween are movable with respect to said second cross member and said at least one elongated member fixedly coupled to said second cross member. 
   
   
     7. The electrical switching apparatus of  claim 6  wherein said at least one elongated member is a first rod and a second rod; wherein said number of springs of said cradle assembly is a first spring disposed on said first rod, and a second spring disposed on said second rod; and wherein said first spring and said second spring bias said cradle assembly toward said second position. 
   
   
     8. The electrical switching apparatus of  claim 5  wherein the first side of said cradle assembly further comprises a protrusion extending outwardly from the first side of said cradle assembly toward said first side plate; wherein said rigid element is pivotably coupled to the second side of said first side plate; and wherein, when said cradle assembly moves toward said second position, said protrusion engages and moves said rigid element. 
   
   
     9. The electrical switching apparatus of  claim 8  wherein said operating mechanism of said electrical switching apparatus further includes a trip lever; and wherein, when said protrusion engages and moves said rigid element and said cradle assembly continues to move toward said second position, said rigid element engages the second end of said reset lever and pivots said reset lever about said pivot, in order that the first end of said reset lever moves said actuating element of said trip actuator. 
   
   
     10. A trip actuator reset assembly for an electrical switching apparatus including a housing, separable contacts enclosed by said housing, and an operating mechanism structured to open and close said separable contacts, said operating mechanism including a pole shaft, said trip actuator reset assembly comprising:
 a cradle assembly including a first end structured to be pivotably coupled to said pole shaft, a second end disposed opposite and distal from the first end, and a number of springs disposed between the first end and the second end, said cradle assembly being structured to be movable among a first position corresponding to said separable contacts being closed, and a second position corresponding to said separable contacts being open; 
 a reset lever including a first end, a second end disposed opposite and distal from the first end of said reset lever, and a pivot structured to pivotably couple said reset lever to said housing; 
 a trip actuator including an actuating element which, in response to a trip condition, is structured to move the first end of said reset lever; 
 a rigid element structured to be pivotably coupled to said housing proximate the second end of said reset lever; 
 a guide member; 
 wherein, after said trip condition, said actuating element of said trip actuator is structured to be reset; 
 wherein, when said cradle assembly moves from said first position toward said second position, said guide member guides said cradle assembly into engagement with said rigid element which pivots said reset lever; 
 wherein, when said rigid element pivots said reset lever, the first end of said reset lever moves said actuating element of said trip actuator, thereby resetting said trip actuator; 
 wherein, after said trip actuator has been reset, if said cradle assembly continues to move beyond said second position, then said number of springs of said cradle assembly accommodate any additional motion of said cradle assembly; 
 wherein said housing of said electrical switching apparatus includes a mounting surface, a first side plate extending outwardly from said mounting surface, and a second side plate extending outwardly from said mounting surface; wherein said guide member includes a first end, a second end disposed opposite and distal from the first end of said guide member, and an elongated body extending between the first end of said guide member and the second end of said guide member; and wherein said elongated body is structured to extend between said first side plate and said second side plate; 
 wherein said first side plate includes a first side and a second side; wherein said actuating element of said trip actuator is structured to be disposed on the first side of said first side plate; and wherein said pivot of said reset lever is structured to be pivotably coupled to the first end of said guide member at or about the first side of said first side plate; 
 wherein said cradle assembly comprises a first side structured to extend from said pole shaft toward the second end of said cradle assembly, a second side disposed opposite and spaced from the first side of said cradle assembly, a first cross member disposed proximate the first end of said cradle assembly, a second cross member disposed at or about the second end of said cradle assembly, and at least one elongated member fixedly coupled to said second cross member and extending through said first cross member; wherein said first cross member extends between the first side of said cradle assembly and the second side of said cradle assembly; wherein said first cross member does not move independently with respect to the first side of said cradle assembly and the second side of said cradle assembly; and wherein said second cross member is structured to extend between and be pivotably coupled to said first side plate and said second side plate, thereby providing a fixed pivot point for said cradle assembly with respect to said first side plate and said second side plate; 
 wherein the first side of said cradle assembly further comprises a protrusion extending outwardly from the first side of said cradle assembly toward said first side plate; wherein said rigid element is pivotably coupled to the second side of said first side plate; and wherein, when said cradle assembly moves toward said second position, said protrusion engages and moves said rigid element; 
 wherein said operating mechanism of said electrical switching apparatus further includes a trip lever; and wherein, when said protrusion engages and moves said rigid element and said cradle assembly continues to move toward said second position, said rigid element engages the second end of said reset lever and pivots said reset lever about said pivot, in order that the first end of said reset lever moves said actuating element of said trip actuator; and 
 wherein, in response to said trip condition, said actuating element of said trip actuator is structured to extend in order to pivot said reset lever and said trip lever; wherein, after said trip condition, said actuating element remains extended until it is depressed by said reset lever in order to reset said trip actuator and said trip lever; wherein said rigid element includes a first end pivotably coupled to the second side of said first side plate, a second end disposed opposite and distal from the first end, and an intermediate portion extending between the first end and the second end; wherein, when said cradle assembly is moved toward said second position, said intermediate portion of said rigid element engages the second end of said reset lever, thereby pivoting said reset lever; wherein, as said cradle assembly moves into said second position, said reset lever is structured to continue to pivot until the first end of said reset lever completely depresses said actuating element, thereby resetting said trip actuator and said trip lever; and wherein, after said trip actuator is reset, if said cradle assembly continues to move, then said number of springs of said cradle assembly absorb such movement. 
 
   
   
     11. An electrical switching apparatus comprising:
 a housing; 
 separable contacts enclosed by said housing; 
 an operating mechanism structured to open and close said separable contacts, said operating mechanism including a pole shaft; and 
 a trip actuator reset assembly comprising:
 a cradle assembly including a first end pivotably coupled to said pole shaft, a second end disposed opposite and distal from the first end, and a number of springs disposed between the first end and the second end, said cradle assembly being movable among a first position corresponding to said separable contacts being closed, and a second position corresponding to said separable contacts being open, 
 a reset lever including a first end, a second end disposed opposite and distal from the first end of said reset lever, and a pivot pivotably couple said reset lever to said housing, 
 a trip actuator including an actuating element which, in response to a trip condition, moves the first end of said reset lever, 
 a rigid element pivotably coupled to said housing proximate the second end of said reset lever, and 
 a guide member, 
 wherein, after said trip condition, said actuating element of said trip actuator must be reset, 
 wherein, when said cradle assembly moves from said first position toward said second position, said guide member guides said cradle assembly into engagement with said rigid element which pivots said reset lever, 
 wherein, when said rigid element pivots said reset lever, the first end of said reset lever moves said actuating element of said trip actuator, thereby resetting said trip actuator, and 
 wherein, after said trip actuator has been reset, if said cradle assembly continues to move beyond said second position, then said number of springs of said cradle assembly accommodate any additional motion of said cradle assembly. 
 
 
   
   
     12. The electrical switching apparatus of  claim 11  wherein said housing of said electrical switching apparatus includes a mounting surface, a first side plate extending outwardly from said mounting surface, and a second side plate extending outwardly from said mounting surface; wherein said guide member of said trip actuator reset assembly includes a first end, a second end disposed opposite and distal from the first end of said guide member, and an elongated body extending between the first end of said guide member and the second end of said guide member; and wherein said elongated body extends between said first side plate and said second side plate. 
   
   
     13. The electrical switching apparatus of  claim 12  wherein said first side plate includes a first side and a second side; wherein said actuating element of said trip actuator is disposed on the first side of said first side plate; and wherein said pivot of said reset lever is pivotably coupled to the first end of said guide member at or about the first side of said first side plate. 
   
   
     14. The electrical switching apparatus of  claim 13  wherein said reset lever further includes a bias element; wherein said first side plate further includes a hole; wherein the second end of said reset lever extends from the first side of said first side plate through said hole of said first side plate and beyond the second side of said first side plate; and wherein said bias element is disposed within said hole of said first side plate, in order to bias the second end of said reset lever away from said actuating element of said trip actuator. 
   
   
     15. The electrical switching apparatus of  claim 13  wherein said cradle assembly comprises a first side extending from said pole shaft toward the second end of said cradle assembly, a second side disposed opposite and spaced from the first side of said cradle assembly, a first cross member disposed proximate the first end of said cradle assembly, a second cross member disposed at or about the second end of said cradle assembly, and at least one elongated member fixedly coupled to said second cross member and extending through said first cross member; wherein said first cross member extends between the first side of said cradle assembly and the second side of said cradle assembly; wherein said first cross member does not move with respect to the first side of said cradle assembly and the second side of said cradle assembly; and wherein said second cross member is structured to extend between and be pivotably coupled to said first side plate and said second side plate, thereby providing a fixed pivot point for said cradle assembly with respect to said first side plate and said second side plate. 
   
   
     16. The electrical switching apparatus of  claim 15  wherein, when said cradle assembly is moved toward said second position, the first side of said cradle assembly, the second side of said cradle assembly, and said first cross member extending therebetween are movable with respect to said second cross member and said at least one elongated member fixedly coupled to said second cross member. 
   
   
     17. The electrical switching apparatus of  claim 16  wherein said at least one elongated member is a first rod and a second rod; wherein said number of springs of said cradle assembly is a first spring disposed on said first rod, and a second spring disposed on said second rod; and wherein said fast spring and said second spring bias said cradle assembly toward said second position. 
   
   
     18. The electrical switching apparatus of  claim 15  wherein the first side of said cradle assembly further comprises a protrusion extending outwardly from the first side of said cradle assembly toward said first side plate; wherein said rigid element is pivotably coupled to the second side of said first side plate; wherein, when said cradle assembly moves toward said second position, said protrusion engages and moves said rigid element; and wherein, when said protrusion engages and moves said rigid element and said cradle assembly continues to move toward said second position, said rigid element engages the second end of said reset lever and pivots said reset lever about said pivot, in order that the first end of said reset lever moves said actuating element of said trip actuator. 
   
   
     19. The electrical switching apparatus of  claim 18  wherein said actuating element of said trip actuator is a plunger; wherein, in response to said trip condition, said plunger extends in order to move said reset lever and said trip lever; wherein, after said trip condition, said plunger remains extended until it is depressed by said reset lever in order to reset said trip actuator and said trip lever; wherein said rigid element includes a first end pivotably coupled to the second side of said first side plate, a second end disposed opposite and distal from the first end, and an intermediate portion extending between the first end and the second end; wherein, when said cradle assembly is moved toward said second position, said intermediate portion of said rigid element engages the second end of said reset lever, thereby pivoting said reset lever; wherein, as said cradle assembly moves into said second position, said reset lever continues to pivot until the first end of said reset lever completely depresses said plunger, thereby resetting said trip actuator and said trip lever; and wherein, after said trip actuator is reset, if said cradle assembly continues to move, then said number of springs of said cradle assembly absorb such movement. 
   
   
     20. The electrical switching apparatus of  claim 11  wherein said electrical switching apparatus is a circuit breaker; wherein said operating mechanism of said circuit breaker further comprises a trip bar and a trip lever extending outwardly from said trip bar; wherein said trip lever includes a fast end, which overlays said actuating element of said trip actuator, and a second end being coupled to said trip bar; and wherein the first end of said trip lever is cooperable with the first end of said reset lever of said trip actuator reset assembly. 
   
   
     21. The trip actuator reset assembly of  claim 10  wherein, after said trip actuator is reset, if said cradle assembly continues to move, then said number of springs are extendable in order to accommodate such movement, without requiring said reset lever to continue to pivot.